Exercise equipment for conditioning the leg muscles has existed in a variety of forms. The majority of such exercise equipment has been large, bulky, and expensive, and not intended to be easily stored and retrieved by the user. For example, reference may be made to U.S. Pat. Nos. 3,920,240; 4,176,836; 4,374,519; 4,700,945; 4,911,432 and 5,162,030.
Early attempts to provide a compact, inexpensive, and convenient exercise device, which is disclosed in U.S. Pat. No. 4,700,945, and which includes a platform adapted to be worn by the user and provided with a set of castors on the back surface of the platform to provide platform mobility. The user attaches the wheeled platform to his or her back, and then performs leg exercising maneuvers by causing the platform to move up and down rollably along a wall, as the user performs knee bends repeatedly, across a stationary surface, thereby exercising the thigh muscles of the user.
Although such an exercise device may be somewhat compact in size, it may not be entirely satisfactory for some applications. In this regard, the platform may be generally unstable due to the set of castors. It would appear that it may well be difficult for the user to maintain all four wheels in simultaneous engagement with the wall, as the device moved upwardly and downwardly repeatedly. The user may have to exert unnecessary and unwanted energy to steer the platform during the performance of an exercise routine.
Such an exercise device was not transported easily, nor was it stored easily. In this regard, the heavy castors or wheels and the associated mounting hardware added excessive weight and bulk to the device. Moreover, the castors could damage the surface of a wall, by scuffing or gauging it unintentionally.
Thus, it would be highly desirable to have a new and improved exercise apparatus, which maneuvered easily, and which is light in weight and relatively compact in size. Such a new and improved exercise apparatus should also move freely over an associated support surface such as a wall, without tending to mar or otherwise to damage it.
Another problem associated with the exercise device described in U.S. Pat. No. 4,700,945 relates to its back engaging platform. In this regard, the patented platform is substantially flat and engages only a portion of the lower back of the user. As a result, only portions of the platform could contact the back of the user due to the shape of the lower back. As a result, the pressure exerted on the back by the platform, would not be uniformly distributed, and thus the user could experience unwanted discomfort during exercising.
Therefore, it would be highly desirable to have a new and improved exercise apparatus, which is comfortable to use and which does not cause unnecessary back discomfort during use.